A referring domain is a separate website that links to yours at least once. If a local newspaper links to your site from five different articles, that counts as five backlinks but only one referring domain.
How referring domains work
Link tools count backlinks and referring domains separately because they tell you different things. Backlinks count every individual link. Referring domains count the number of distinct websites those links come from, so they show how widely your site is cited across the web rather than how many times one site happens to mention you.
The difference can be large. A site with 3,000 backlinks might have them from only 40 domains, because one directory or partner links from the footer of every page. Another site with 300 backlinks might have them from 200 different domains. The second usually has the stronger link profile, because it is endorsed independently by many more sources.
Tools also differ in what they count as a domain. Ahrefs, Semrush and Majestic each crawl the web separately, so their numbers will not match one another or Google’s. They also handle subdomains differently, so a university or a large publisher with many subdomains may count once in one tool and several times in another. Google Search Console’s Links report shows your “top linking sites”, which is the closest view you have of what Google itself has found, though it is a sample rather than a complete list.
Why it matters
Google describes links from other websites as one of the ways it judges how useful and trustworthy a page is. Each independent site that chooses to link to you is a separate endorsement, and many separate endorsements say more than repeated ones from a single source.
For a UK business, the number on its own matters less than which domains they are. One link from a respected trade association, a regional newspaper or a university department can be worth more than dozens from directories nobody visits. A Leeds architect cited by the Royal Institute of British Architects, a local business award site and two property news sites has a better profile than one listed on fifty generic web directories.
Referring domains are also a useful way to compare yourself with competitors. If every firm in the top three for your main service has links from 150 to 300 domains and you have 20, content and technical work alone may not close the gap.
Common mistakes
- Chasing a number. Buying links or submitting to bulk directories inflates the count with domains that carry no weight and can create risk.
- Treating third-party scores as Google’s view. Domain Rating and similar metrics estimate link strength; Google does not use them.
- Ignoring relevance. Links from sites in your sector and region usually matter more than links from unrelated sites with high scores.
- Panicking about every low-quality domain. Every site attracts some spammy links. Google is good at ignoring them, and most do not need disavowing.
- Losing domains without noticing. Links disappear when partners redesign or articles are removed. Track lost referring domains as well as new ones.
How to act on it
Start by exporting referring domains from Search Console’s Links report and from one third-party tool, such as those covered in Ahrefs and Semrush. Sort them into genuine, relevant sites and noise. Then run the same check on two or three competitors and list domains that link to several of them but not to you: trade bodies, suppliers, local organisations, industry publications. These are your most realistic targets.
Grow the count through work that earns new sites rather than more links from the same ones: useful resources others want to cite, expert comment for journalists through digital PR, and memberships and partnerships that come with a listing. Check new and lost referring domains each month. Planning that work so every new link is safe and relevant is what my link building service does.